Field of the Invention
This invention relates to thermoplastic adhesives and more particularly to thermoplastic-polyimide (TPI) A-staged adhesives.
Description of the Prior Art
The employment of partially cured (B-stage) or fully cured (C-stage) TPI compounds disposed on substrates as adhesives are known in the prior art. However, as best known to the inventor, it is unknown to use the precursor of these compounds in an uncured (A-stage) state, either with or without suitable fillers for bonding purposes by applying the uncured TPI precursor in liquid form (A-stage) directly to the surfaces to be joined and thereafter curing entirely In Situ or at the site.
As described below the use of the A-staged TPI adhesive of the invention may be particularly useful in, for example, the fields of lamination of a semiconductor die to an aluminum heat sink (die-attachment) for thermal management of high-power electronic packaging and, additionally, the bonding of superconducting coils.